The present disclosure relates to a zero turn radius (ZTR) mower. More specifically, the present disclosure relates to a ZTR mower that includes an electric powertrain including a one or more electric storage batteries, a plurality of electric wheel drive motors and a plurality of electric blade motors.
ZTR mowers have become a popular type of lawn mowing equipment and include a pair of independently driven rear wheels. The independent drive of the rear wheels allows the ZTR mower to be extremely maneuverable and operable at relative high mowing speeds. ZTR mowers are popular with landscaping companies and homeowners that have a substantial amount of acreage to mow on a regular basis.
ZTR mowers typically include an internal combustion engine that transfers drive power through hydrostatic transaxles to the pair of drive wheels. Each of the drive wheels are independently driven at different speeds and even in different directions, which creates the extreme maneuverability of the ZTR mower.
Recently, outdoor power equipment manufacturers, like many other industries, have embraced the trend of utilizing electric storage batteries as an alternate power supply to gas powered engines. In order to use a battery power supply, the hydrostatic drive motors in ZTR motors must be removed and replaced by separate electric wheel drive motors for each of the two rear drive wheels as well as one or more electric motors for rotating the plurality of mowing blades. Since multiple electric motors must be utilized, a complex control system must be employed to accurately control and synchronize the rotational speed of the electric blade motors and the speed and direction of the electric wheel motors. The present disclosure provides a control system for controlling the rotational speed of all of the electric motors utilized in an electric ZTR mower.